Correction fluid



United States Patent Ofitice 3,299,808 Patented Jan. 24, 1967 3,299,808 CORRECTION FLUID Arthur Zitt, 81 Woodview Road, West Hempstead, N.Y. 11552 No Drawing. Filed Aug. 12, 1965, Ser. No. 479,305 9 Claims. (Cl. 101--149.4)

The present invention relates to a correction fluid. More particularly, it is concerned with a correction fluid for preparing a master unit employed in the spirit duplicating process.

It is known to use a spirit master unit in conjunction with a spirit duplicator (US. No. 3,177,086). The master unit may have a transfer sheet which is coated with dye and a vehicle for the dye, e.g., wax, and a master sheet which is adjacent to the coating on the transfer sheet. An impression is formed by applying pressure to the transfer sheet with a pen, pencil, typewriter or the like, and the dye and wax is transferred to the master sheet. The master sheet with the dye thereon is separated from the transfer sheet and is placed subsequently on a spirit duplicator containing an alcohol, e.g., ethyl alcohol, solvent. The paper to be imprinted is passed through the spirit duplicator and is moistened by the alcohol solvent. The moistened p-aper then contacts in rotary motion the master sheet with the dye thereon, and a small part of the dye is transferred from the master sheet to the moistened paper. In this manner, the impression applied originally to the transfer sheet has been duplicated on the moistened paper. One master sheet is capabio of providing numerous copies by passin more paper through the spirit duplicator.

During the formation of the impression on the master unit, an error or undesirable area, such as a typing error, may occur. This error appears, therefore, on the master sheet, and it must be corrected before the master sheet is laced on the spirit duplicator. Otherwise, the error will appear on the paper which is passed through the spirit duplicator.

In the past, several methods have been employed to correct errors on the master sheet. One method is to scrape with a knife the dye and wax on the master sheet corresponding to the error. Another method is to use a white pencil or white liquid to cover the erroneous dye on the master sheet. Still another method is to place a strip of paper with an adhesive backing on top of the erroneous dye on the master sheet. After the dye and wax have been scraped or covered, pressure is reapplied to the transfer sheet, for example by retyping, and dye and wax are transferred to the scraped or covered area on the master sheet. The aforementioned methods previously used to correct errors on the master sheet have not been entirely satisfactory since they are extremely dirty and/or they create an uneven surface on the master unit. Consequently, a poor correction is found on the final copy, i.e., the imprinted paper after passing through the spirit duplicator.

It has now been discovered that the errors on a spirit master sheet can be corrected without the disadvantages of the prior art methods. Thus, in accordance with one embodiment of the invention, a correction fluid is provided having a borohydride and a solvent. The borohydride-containing correction fluid is applied to the dye on the master sheet corresponding to the error in order to bleach out the color of the erroneous dye and to dissolve the dye vehicle thereon. This provides after drying a clean, even surface without any trace of dye and dye vehicle. After retyping or the like, dye and dye vehicle are transferred to this surface and the correction is not evident on the final copy.

The correction fluid of the present invention contains a borohydride. Any borohydride that is capable of bleaching the dye on the master sheet may be used. This includes both alkali and acid borohydrides, such as alkali metal borohydrides and tetraalkyl ammonium borohydrides, and mixtures of two or more borohydrides. The following borohydrides among others are suitable: sodium borohydride, potassium borohydride, lithium borohydride, tetramethyl ammonium borohydride, tetraethyl ammonium borohydride, tetraisopropyl ammonium borohydride, tetrabutyl ammonium borohydride, tetraamyl ammonium borohydride, tricapryl methyl ammonium borohydride, morpholine borane and mixtures thereof. Any amount of borohydride can be used in the correction fluid provided that the amount is suflicient to bleach the erroneous dye on the master sheet. Generally, the correction fluid has an amount up to about 10% by weight borohydride, preferably about 2% to 5% by weight. The borohydride may be prepared by any acceptable method, such as the methods disclosed in US. Pat. Nos. 2,970,114 and 3,108,139 which are included herein by reference.

A solvent is an essential ingredient in the borohydridecontaining correction fluid. As stated heretofore, the coating on the transfer sheet has a dye and also a vehicle for carrying the dye. The dye vehicle may be wax, a wax derivative, a resin and the like. When dye is transferred to the master sheet, dye vehicle is also transferred to the master sheet. In order to make a clean correction, it is necessary to remove the dye vehicle from the master sheet. Therefore, any material which is both a solvent for the active borohydriide and a solvent for the dye vehicle, e.g., wax, is suitable for this invention. The following solvents among others are applicable: isopropanol, methyl alcohol, ethyl alcohol, butyl alcohol, trichloroethylene, triethane(l,1,1 trich loroethane), methylene chloride, chloroethane, petroleum ether, hexane, pentane, dimethyl ether of ethylene glycol and mixtures thereof. The balance of the correction fluid is solvent and the amount may vary over a wide range, e.g., an amount up to about 95% by weight, preferably about 50% to by weight. However, the

amount of solvent must be suflicient to dissolve the boro hydride in the correction fluid and to dissolve the erroneous dye vehicle on the master unit.

The correction fluid of the invention may have, when necessary, a material therein to stabilize the solution of borohydride in solvent. Any satisfactory stabilizer may be used, such as dimethyl formamide, sodium methylate, sodium hydroxide, triethanolarnine, diethylamine, butylamine and mixtures thereof. Any stabilizing amount may be employed in the correction fluid. Generally, the correction fluid has up to about 50% by weight stabilizer, e.g., about 5% to 50% by weight.

In the present invention, the preferred correction fluids zre Formulations A, B, C and D which are indicated hereelow.

Formulation A Ingredients: Parts (by wt.) Sodium borohydride 35 Isopropanol 38-4O Methanol 50 Sodium hydroxide 5 Water l0 Formulation B Ingredients: Parts (by wt.) Hydroquat B8 1 2-4 Dimethyl formamide 10 Triethane 86-88 1 Tricapryl methyl ammonium borohydride.

Formulation C Ingredients: Parts (by wt.) Tetraethyl ammonium borohydride 3-5 Isopropanol 50 Methylene chloride 45-47 Formulation D Ingredients: Parts (by wt.) Morpholine borane 2-4 Monoglyme 1 Benzene 2O Ethanol 4648 1 Diinethyl ether of ethylene glycol.

The correction fluid 0f the invention can be used in conjunction with any spirit master unit having a hectograph transfer sheet and a master sheet. The transfer sheet is coated with a dye, e.g., an aniline dye, a dye vehicle, e.g., a wax or resin, and other optional ingredients. The coating for a transfer sheet may have a synthetic thermoplastic film-forming binder, a miscible mixture of oleaginous modifying agents and a spiritsolub le hectograph dye as described in US. Pat. No. 3,177,086 which is included herein by reference. This coating is transferable to the master sheet in the master unit'in an area impressed with imaging pressure.

When an error, e.g., typing error, is made, the correction fluid is applied to the corresponding dye and dye vehicle on the surface of the master sheet. Within a short period of time, e.g., a few seconds, the dye has been bleached and the wax or other dye vehicle has been dissolved. After drying the surface is even and clean, and it does not have any erroneous dye and dye vehicle thereon. A correct impression is formed on the aforementioned clean surface of the master sheet by retyping or by reapplying other pressure to the transfer sheet whereby the desired dye and dye vehicle are transferred to the master sheet.

The corrected master sheet apart from the transfer sheet is placed on a cylinder in the spirit duplicator. The spirit duplicator contains a solvent, e.g., methyl alcohol, ethyl alcohol, ethylene glycol monoethy-l ether, water and mixtures thereof, for the dye on the master sheet. The paper to be imprinted is placed on a tray and is passed through the spirit duplicator. As the paper passes through the spirit duplicator, it is moistened with solvent by means of a saturated wick or spray pump, and the moistened paper contacts the master sheet in rotary motion. This causes a transfer of part of the dye on the master sheet to the paper and a copy is provided therefrom. There is no evidence on the copy of any correction having been made on the master sheet.

Thus, in accordance with this invention, a fluid has been formed which is capable of correcting an error on a spirit master sheet to provide a surface that is clean and even. Furthermore, the correction is not evident on the final copy which has contacted the master sheet as it has passed through a spirit duplicator.

The following example is submitted to illustrate but not to limit this invention. Unless otherwise indicated, all parts and percentages in the specification and claims are based upon weight.

4 EXAMPLE 1 Correction fluids were prepared with the following ingredients therein.

Correction Fluids (parts by wt.) Ingredients Sodium borohydride Hydroquat B8 Tetraethyl ammonium borohydride Morpholine borane Isopropanol Dimethyl formamide. Triethane Methylene chloride. Monogly1ne Benzene.

Ethanol Spirit master units having master sheets and hectograph transfer sheets containing aniline dye and wax were placed separately in a typewriter. After typing several words, the master sheet had the typed words thereon since dye and wax were transferred from the transfer sheet to the master sheet. 7

Each of the above correction fluids was applied independently to the dye and wax on a master sheet corresponding to a single letter of typing. After a few seconds, the applied surface on each master sheet was dried with absorbent cotton, and there was no trace of the singlev letter since the dye had been bleached out and the wax had been dissolved by each correction fluid.

A different letter was typed on each spirit master unit to form transferred dye and wax on the master sheet in the same space where the previous letter had appeared. Each corrected master sheet therefrom had a clean and even surface in the area corresponding to the retyped letter.

Subsequently, the corrected spirit master sheets were placed independently in a spirit duplicator containing methanol as :a solvent. After passing paper, which had been moistened with the solvent and which had been contacted with each corrected spirit master sheet, through the spirit duplicator, a copy was obtained corresponding to each corrected spirit master sheet. There was no evidence of the corrections on any of the copies.

Having set forth the general nature and specific embodiments of the present invention, the true scope is now particularly pointed out in the appended claims.

What is claimed is:

1. A process for correcting an error on a spirit master sheet represented by dye and dye vehicle which comprises applying to the dye and dye vehicle a correction fluid comprising a borohydride which is an alkali metal borohydride, a tetraalkyl ammonium borohydride or morpholine borane and a solvent to provide a clean, even surface without any trace of dye and dye vehicle.

2. The process. according to claim 1 in which the correction fluid also contains a stabilizer.

3. The process according to claim 2 in which the stabilizer is selected from the group consisting of dimethyl formjamide, sodium methylate, sodium hydroxide, triethanolamine, diethylamine, butylamine and mixtures thereof.

4. The process according to claim 1 in which the borohydride is selected from the group consisting of sodium borohydride, potassium borohydride, lithium borohydride, tetramethyl ammonium borohydride, tetraethyl ammonium borohydride, tetraisopropyl ammonium borohydride, tetrazbutyl ammonium borohydride, tetraamyl ammoniuum borohydride, tricapryl methyl ammonium borohydride, morpholine borane and mixtures thereof.

5. The process according to claim 1 in which the solvent is selected from the group consisting of isopropanol,

5 methyl alcohol, ethyl alcohol, butyl alcohol, trichloroethylene, methylene chloride, 1,1,1-trichloroethane, chlo1' ethane, petroleum ether, hexane, pentane, dimethyl ether of ethylene glycol and mixtures thereof.

6. A process for correcting an error on a spirit master sheet represented by dye and dye vehicle which comprises applying to the dye and dye vehicle a correction fluid comprising 3 to 5 parts sodium borohydride, 38 to 40 parts isopropanol, 50 parts methanol, 5 parts sodium hydroxide and parts water to provide a clean, even surface without any trace of dye and dye vehicle; forming additional dye and dye vehicle in the same space previously occupied by the erroneous dye and dye vehicle to provide a corrected spirit master sheet; and passing paper to be imprinted through a spirit duplicator in contact with the corrected master sheet to provide a final copy Without any evidence of the correction there- 7. A process for correcting an error on a spirit master sheet represented by dye :and dye vehicle which comprises applying to the dye and dye vehicle a correction fluid comprising 2 to 4 parts tricapryl methyl ammonium borohydride, 10 parts dimethyl formamide and 86 to 88 parts 1,1,1-trichloroethane to provide a clean, even surface without any trace of dye and dye vehicle; forming additional dye and dye vehicle in the same space previously occupied by the erroneous dye and dye vehicle to provide a corrected spirit master sheet; and passing paper to be imprinted through a spirit duplicator in contact with the corrected master sheet to provide a final copy without any evidence of the correction thereon.

8. A process for correcting an error on a spirit master sheet represented by dye and dye vehicle Which comprises applying to the dye and dye vehicle a correction fluid comprising 3 to 5 parts tetraethyl ammonium horohydride, 50 parts isopropanol and to 47 parts methylene chloride to provide a clean, even surface without any trace of dye and dye vehicle; forming additional dye and dye vehicle in the same space previously occupied by the erroneous dye and dye vehicle to provide a corrected spirit master sheet; and passing paper to be imprinted through a spirit duplicator in contact with the corrected master sheet to provide a final copy without any evidence of the correction thereon.

9. A process for correcting an error on a spirit master sheet reprsented .by dye and dye vehicle which comprises applying to the dye vehicle a correction fluid comprising 2 to 4 parts morpholine bor-ane, 30 parts dimethyl ether of ethylene glycol, 20 parts benzene and 46 to 48 parts ethanol to provide a clean, even surface without any trace of dye and dye vehicle; forming additional dye and dye vehicle in the same space previously occupied by the erroneous dye and dye vehicle to provide a corrected spirit master sheet; and passing paper to be imprinted through a spirit duplicator in contact with the corrected master sheet to provide a final copy without any evidence of the correction thereon.

References Cited by the Examiner UNITED STATES PATENTS 2,970,114 1/1961 Bragdon 252188 3,014,025 12/1961 Pearson et al. 252188 3,081,265 3/1963 Burr 252188 3,108,139 10/1963 Larchar 252188 ROBERT E. PULFREY, Assistant Examiner.

I. A. BELL, Assistant Examiner. 

1. A PROCESS FOR CORRECTING AN ERROR ON A SPIRIT MASTER SHEET REPRESENTED BY DYE AND DYE VEHICLE WHICH COMPRISES APPLYING TO THE DYE AND DYE VEHICLE A CORRECTION FLUID COMPRISING A BOROHYDRIDE WHICH IS AN ALKALI METAL BOROHYDRIDE, A TETAALKYL AMMONIUM BOROHYDRIDE OR MORPHOLINE BORANE AND A SOLVENT TO PROVIDE A CLEAN, EVEN SURFACE WITHOUT ANY TRACE OF DYE AND DYE VEHICLE. 